UK researchers have unearthed a new argument in the yes-but-no-but-yes scientific debate about Martian water, saying that meteorite samples suggest water on the red planet was once warm enough for life.

In research published in Earth an Planetary Science Letters (abstract here), Dr John Bridges (Leicester University) and Dr Susanne Schwenzer (Open University) say structures found in a group of meteorites of Martian origin called nakhlites.